2. Section 27.1 Summary – pages 721-727  Mollusks have a well-developed circulatory system that includes a three-chambered heart. Circulation in mollusks Heart

3. Section 27.1 Summary – pages 721-727  In most mollusks, the heart pumps blood through an open circulatory system.  In an open circulatory system, the blood moves through vessels and into open spaces around the body organs. Circulation in mollusks

4. Section 27.1 Summary – pages 721-727  Some mollusks, such as octopuses, move nutrients and oxygen through a closed circulatory system.  In a closed circulatory system, blood moves through the body enclosed entirely in a series of blood vessels. Circulation in mollusks

5. Section 27.1 Summary – pages 721-727  Most mollusks have respiratory structures called gills. Respiration in mollusks  Gills are specialized parts of the mantle that consist of a system of filamentous projections that contain a rich supply of blood for the transport for gases.

6. Section 29.1 Summary – pages 763-769 The water vascular system  The water vascular system is a hydraulic system that operates under water pressure.  Water enters and leaves the water vascular system of a sea star through the madreporite (mah druh POHR ite), a sievelike, disk-shaped opening on the upper surface of the echinoderm’s body.

7. Section 29.1 Summary – pages 763-769 The water vascular system  The underside of a sea star has tube feet that run along a groove on the underside of each ray.

8. Section 29.1 Summary – pages 763-769 The water vascular system  Tube feet are hollow, thin-walled tubes that end in a suction cup.  Tube feet look somewhat like miniature droppers.  The round, muscular structure called the ampulla (AM pew lah) works something like the bulb of a dropper.

9. Section 29.1 Summary – pages 763-769 The water vascular system  Each tube foot works independently of the others, and the animal moves along slowly by alternately pushing out and pulling in its tube feet. Ampullae

10. Section 29.1 Summary – pages 763-769 The water vascular system  Tube feet also function in gas exchange and excretion. Gases are exchanged and wastes are eliminated by diffusion through the thin walls of the tube feet.

11. Section 28.1 Summary – pages 741 - 746  This large oxygen demand is needed to sustain the high levels of metabolism required for rapid movements. Arthropods have efficient gas exchange  Arthropods have efficient respiratory structures that ensure rapid oxygen delivery to cells.

12. Section 28.1 Summary – pages 741 - 746  Three types of respiratory structures have evolved in arthropods: gills, tracheal tubes, and book lungs. Arthropods have efficient gas exchange

13. Section 28.1 Summary – pages 741 - 746  Aquatic arthropods exchange gases through gills, which extract oxygen from water and release carbon dioxide into the water. Arthropods have efficient gas exchange

14. Section 28.1 Summary – pages 741 - 746  Land arthropods have either a system of tracheal tubes or book lungs. Arthropods have efficient gas exchange

15. Section 28.1 Summary – pages 741 - 746  Most insects have tracheal tubes, branching networks of hollow air passages that carry air throughout the body. Arthropods have efficient gas exchange

16. Section 28.1 Summary – pages 741 - 746  Air enters and leaves the tracheal tubes through openings on the thorax and abdomen called spiracles.  Muscle activity helps pump the air through the tracheal tubes. Arthropods have efficient gas exchange

17. Section 28.1 Summary – pages 741 - 746  Most spiders and their relatives have book lungs, air-filled chambers that contain leaflike plates. Arthropods have efficient gas exchange

18. Section 28.1 Summary – pages 741 - 746  The stacked plates of a book lung are arranged like pages of a book. Arthropods have efficient gas exchange

19. Section 30.1 Summary – pages 793-802  Fishes have gills made up of feathery gill filaments that contain tiny blood vessels. Fishes breathe using gills Gill Filaments

20. Section 30.1 Summary – pages 793-802  As a fish takes water in through its mouth, water passes over the gills and then out through slits at the side of the fish. Fishes breathe using gills Gill Filaments Capillary networks in filament Gillfilaments Water Water Artery Vein

21. Section 30.1 Summary – pages 793-802 Fishes breathe using gills  Oxygen and carbon dioxide are exchanged through the capillaries in the gill filaments. Gill Filaments Gillfilaments Water Water Artery Vein Capillary networks in filament

22. Section 30.1 Summary – pages 793-802 Fishes have two-chambered hearts Heart Gills Aorta Capillarynetwork

23. Section 31.2 Summary – pages 826 - 833 Flight requires energy  Flight requires high levels of energy.  Several factors are involved in maintaining these high energy levels.

24. Section 31.2 Summary – pages 826 - 833 Flight requires energy  First, a bird’s four- chambered, rapidly beating heart moves oxygenated blood quickly throughout the body.  This efficient circulation supplies cells with the oxygen needed to produce energy.

25. Section 31.2 Summary – pages 826 - 833 Flight requires energy  Second, a bird’s respiratory system supplies oxygenated air to the lungs when it inhales as well as when it exhales.  A bird’s respiratory system consists of lungs and anterior and posterior air sacs.

26. Section 31.2 Summary – pages 826 - 833 Flight requires energy  During inhalation, oxygenated air passes through the trachea and into the lungs, where gas exchange occurs. Trachea Anterior air sacs Lung Posterior air sacs Anterior air sacs Key: Breathing cycles Cycle 1 Inhalation 1 Exhalation 2 Inhalation 1 Cycle 2 Exhalation 2

27. Section 31.2 Summary – pages 826 - 833  Most of the air, however, passes directly into the posterior air sacs. Trachea Anterior air sacs Lung Posterior air sacs Anterior air sacs Key: Breathing cycles Cycle 1 Inhalation 1 Exhalation 2 Inhalation 1 Cycle 2 Exhalation 2 Flight requires energy

28. Trachea Anterior air sacs Lung Posterior air sacs Anterior air sacs Key: Breathing cycles Cycle 1 Inhalation 1 Exhalation 2 Inhalation 1 Cycle 2 Exhalation 2 Section 31.2 Summary – pages 826 - 833  When a bird exhales deoxygenated air from the lungs, oxygenated air returns to the lungs from the posterior air sacs. Flight requires energy

29. Section 31.2 Summary – pages 826 - 833  At the next inhalation, deoxygenated air in the lungs passes into the anterior air sacs. Trachea Anterior air sacs Lung Posterior air sacs Anterior air sacs Key: Breathing cycles Cycle 1 Inhalation 1 Exhalation 2 Inhalation 1 Cycle 2 Exhalation 2 Flight requires energy

30. Section 31.2 Summary – pages 826 - 833  Finally, at the next exhalation, air passes from the anterior air sacs out of the trachea. Thus, air follows a one-way path in a bird. Trachea Anterior air sacs Lung Posterior air sacs Anterior air sacs Key: Breathing cycles Cycle 1 Inhalation 1 Exhalation 2 Inhalation 1 Cycle 2 Exhalation 2 Flight requires energy

31. Section 30.2 Summary – pages 803-809 The laborious walking of early amphibians required a great deal of energy from food and large amounts of oxygen for aerobic respiration. Walking requires more energy The evolution of the three-chambered heart in amphibians ensured that cells received the proper amount of oxygen.

32. Section 30.2 Summary – pages 803-809 In the three-chambered heart of amphibians, one chamber receives oxygen-rich blood from the lungs and skin, and another chamber receives oxygen-poor blood from the body tissues. Walking requires more energy

33. Section 30.2 Summary – pages 803-809 Blood from both chambers then moves to the third chamber, which pumps oxygen-rich blood to body tissues and oxygen-poor blood back to the lungs and skin so it can pick up more oxygen. Walking requires more energy

34. Section 30.2 Summary – pages 803-809 Because the skin of an amphibian must stay moist to exchange gases, most amphibians are limited to life on the water’s edge or other moist areas. Walking requires more energy

35. Section 31.1 Summary – pages 817 - 825  Most reptiles have three-chambered hearts. Some reptiles have four-chambered hearts  Some reptiles, notably the crocodilians, have a four-chambered heart that completely separates the supply of blood with oxygen from blood without oxygen.  This separation is an adaptation that supports a higher level of energy use required by land animals.

36. Section 31.1 Summary – pages 817 - 825  All reptiles have internal fertilization. In most cases, the eggs are laid after fertilization and embryos develop after eggs are laid. Some reptiles have four-chambered hearts

37. Section 31.1 Summary – pages 817 - 825  Most reptiles provide no care for hatchlings, but female crocodiles have been observed guarding their nests from predators. Some reptiles have four-chambered hearts

38. Section 32.1 Summary – pages 841 – 847 Respiration and circulation in mammals  The mammals’ diaphragm helps expand the chest cavity to aid the flow of oxygen into their lungs. Position of diaphragm when exhaling Position of diaphragm when inhaling Position of ribs when exhaling Lungs when exhaling Position of ribs when inhaling Lungs when inhaling

39.  A diaphragm is the sheet of muscle located beneath the lungs that separates the chest cavity from the abdominal cavity, where other organs are located. Section 32.1 Summary – pages 841 - 847 Position of diaphragm when exhaling Position of diaphragm when inhaling Respiration and circulation in mammals

40. Section 32.1 Summary – pages 841 - 847  Mammals have four-chambered hearts in which oxygenated blood is kept entirely separate from deoxygenated blood. Right atrium Right ventricle Left atrium Left ventricle Respiration and circulation in mammals

41. Section 32.1 Summary – pages 841 - 847  Circulation also removes waste products from cells and helps regulate body temperature.  Blood helps keep a constant cellular environment, which maintains homeostasis. Respiration and circulation in mammals

42. 1)Compare and contrast gills and lungs 2) What components do all gas exchange systems have? 3) Define tracheal tubes 4) Why do some animals have simple system and some complex 5)Compare and contrast open and closed circulatory system

43. 6) List all of the possible ways animals can capture O 2 from the air 7) What factors shape the type and complexity of the system